<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>D-文字排版</title>
    <style>
        .demo{
            background: #ccc;
            width: 100px;
            height: 100px;
            margin-bottom: 10px;

            letter-spacing:5px;
        }
        .demo-1{
            /*word-break:break-all;*/
            word-wrap: break-word;
        }

        .demo-2{
            background: #ccc;
            width: 100px;
            height: 100px;
            word-break: keep-all;
        }
    </style>


</head>
<body>
<div class="demo">
    class.imooc.com class.imooc.com
</div>
<div class="demo demo-1">
    class.imooc.com class.imooc.com
</div>
<div class="demo-2">
    class.imooc.com class.imooc.com
</div>
</body>
</html>